Imperial College London
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Professor Gareth Collins

Faculty of Engineering, Department of Earth Science & Engineering

Professor of Planetary Science
 
 
 
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Contact

 

+44 (0)20 7594 1518g.collins Website

 
 
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Location

 

4.83Royal School of MinesSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Luther:2018:10.1111/maps.13143,
author = {Luther, R and Zhu, M-H and Collins, GS and Wunnemann, K},
doi = {10.1111/maps.13143},
journal = {Meteoritics and Planetary Science},
pages = {1705--1732},
title = {Effect of target properties and impact velocity on ejection dynamics and ejecta deposition},
url = {http://dx.doi.org/10.1111/maps.13143},
volume = {53},
year = {2018}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - Impact craters are formed by the displacement and ejection of target material. Ejection angles and speeds during the excavation process depend on specific target properties. In order to quantify the influence of the constitutive properties of the target and impact velocity on ejection trajectories, we present the results of a systematic numerical parameter study. We have carried out a suite of numerical simulations of impact scenarios with different coefficients of friction (0.0–1.0), porosities (0–42%), and cohesions (0–150 MPa). Furthermore, simulations with varying pairs of impact velocity (1–20 km s−1) and projectile mass yielding craters of approximately equal volume are examined. We record ejection speed, ejection angle, and the mass of ejected material to determine parameters in scaling relationships, and to calculate the thickness of deposited ejecta by assuming analytical parabolic trajectories under Earth gravity. For the resulting deposits, we parameterize the thickness as a function of radial distance by a power law. We find that strength—that is, the coefficient of friction and target cohesion—has the strongest effect on the distribution of ejecta. In contrast, ejecta thickness as a function of distance is very similar for different target porosities and for varying impact velocities larger than ~6 km s−1. We compare the derived ejecta deposits with observations from natural craters and experiments.
AU  - Luther,R
AU  - Zhu,M-H
AU  - Collins,GS
AU  - Wunnemann,K
DO  - 10.1111/maps.13143
EP  - 1732
PY  - 2018///
SN  - 1086-9379
SP  - 1705
TI  - Effect of target properties and impact velocity on ejection dynamics and ejecta deposition
T2  - Meteoritics and Planetary Science
UR  - http://dx.doi.org/10.1111/maps.13143
UR  - http://hdl.handle.net/10044/1/61154
VL  - 53
ER  -
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